1. Field of the Invention
The present invention relates to a surface emitting semiconductor device.
2. Related Background of the Invention
There are a number of types of current confinement structures for surface emitting lasers, such as vertical cavity surface emitting lasers (VCSELs). Publication (“Basis and Application of Surface Emitting Lasers”, Kenji Iga, Fumio Ogawa, Kyouritsu Publication, pp. 30-31) discloses five types of current confinement structures as follows: (1) ring electrode type; (2) proton implantation type; (3) buried heterostructure type; (4) air post type; and (5) selective oxidation type. Most of VCSELs use types (2) and (5).